Telescope.



F. B. SABGMULLER.

TELESCOPE.

APPLICATION FILED AUG. 28. 1911.

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.' iii-ac su h-ea nslimy- STATES PATENT "rn'n nnnxcnnf sAE'GMt'ILL n, or ROCHESTER, New YORK. assrerionro-Bnnsnas lite 012,715 Specification of Telescop.es; anclgl do liereby declare thefollowing to lbeafnll, clear,,an (l exact deserip tioii. of the;same referenee being had to the,- accompanying draw ngs,forming a. part of this specification, and to'the reference-nus,

lnerals marked thereon, r

3 My-present lnYQlli'iOll relates to telescopes, particularlyofthat type adapted to be used forth sighting of cannon, and it has for its obj'echto provide an instrument of this char,-

act-er inwhich twopersons, suchas the gunner,;,.01: the;ordnance .oflicer or instructor,

- ,may simultaneouslyfl view the same ob ect by observin tivo different images of the object appearingintwo separate eye:pieees or oeulars 'a-ndjf in car ying out my invent on, 1 providelin an; instrument or this character:

means forproperlypositmnmg the image ot the objectpby reflecting or directing only a portion of the light rays into the secondary,

or ofiiceigs,eye-piece, permitting the remaining portion nfi s aidirays to pass into and pert-raya clear View of the object in the pri- Inary or gunners e e-Inere.

s filo-these and' other ends the invention consists in certainimprovements and combinations parts alias will be hereinai'ter more fully described. the novel features being pointed out in the claims at the end of the specification, I H

1In-thedrawings;Figure 1 is a horizontal sectional vie-u 'of atelescope illustrating one (mlbOdilnehtfiflllyil1\'01lti(n1; Fig, 2 is an enlargedsectional View taken on the line 2.-2" vofid ligz 1;}11151} 3 is an enlarged perspective/viewshowing a 'pris1n which may thejeniployed as one. means, for aecom plishing the object-of my invention; Fig. at s an ill-iistr: ition; shearing-.1 Il Ql'Lltl rgred outl inc of the exit pupil of ,one oi the' eye-pieres, formedby;the p 'srn shown in Fig. as 1t appears he esyed at a distance t l iere' item; .l lig I p aeri'e v, siinilar 'to' FigQB; showing hen way in vhich the reflectingsnrfac o the p g-sin nay he made}; and Big; (343 a -1 .111 st atn the taiipear nce of .the'uex pupi to, n'eclb' a; reflect ng sur Fl if; i Similar reference minerals throughout the several'figures indie-a te the same parts.

TELESCOPE.

l Application filed August 28, 191 1. Serial No. 646,328.

' 'IiOMB oP'rIcAIJ c'oMPANY, or ROCHESTER, NEW YORK, A conronAfrxonor Letters Patent Patented 1911;}

Inillustrating my prf cnt" nvention have shown it in connect on il'i tih ii itelescope con'iprising the tubular shell jl to, the outer end of which is fitted la n "(ilij ctiir'e; v lens '2, and having at opfitisitel entl tlieffao primary eyepiece, or ocular; 3; ommi te any preferred arrangeinent;fut eye iece; lenses'in relation toivhi'ch he 1i ual hairs are located, as will beifiid t t ii an instrument of. this cliziractenwhen t'ifsflea intended to be used as a sight' it portant that the images "-tjifffobjeiz by the operator appeal'in tl'] right positions, andtherfe therj posed between the objecti' ehiid H p syste'nrof erecting lenses'fcoxi'rprising a'col lective lens l'a'nd the pro e'cting lent secondary ocular, indicated i G, intended" t'or the use of the oliicerfol' 'instiii or,

prises an independent tel'n' ofeYe 1ece..75 .lenses the axis ot' ivliich'extentls angle} to the major axis of the teles eop i-"Tliis" seeondary ocular is supported in the tube 4 I idew li;

7 sin-roundin an aperture in the l of the shell 1, the lenses"being 'suppo ed m a suitable mounting S, atthe inlrie'ii'fid ipf which atulnilar extension!) havingspaced arms 10 and 11 projecting facrossithe' shell' v 1. 'lhesearms are preferably employed the support on which isiinoiinted tli employed for collecting a portion 'ofj'th rays of light passing through th boily of the instrun'ient. and reflectingfthem mt the; secondary ocular. 'lheJlatte'i' is" v I arranged with the axis of itsf'len. angles to the inain axis ofthe t ele ope in rear of the erecting systerhhkif lenses and 5, and as all of'the rays oflight emaiiat' 'ing from all points ofthetfieldcoiteied-by the objective lens 2 passtlii'ougH-allpoints ofthe. exposed portion-,of tl el' ""-5,--i t' -i's possible at this point to fleflect amnion-of the peneilo'f rays into the secondarypcular', and" pern'iitfthe 1 -emainin mys'ef-thspenei1 't'ofipass into ithe jar-marry,ba ling-end still produce in each otbtilar' aeornple'teiitiage'bf the object order,'-'hi*eVer;-'-'to fprewrent 'the rerersal froni right tti'l eftfit is desipable that the rays of"l'iglit be:be'ntf by.fiiii plo f'in g' coact'iii re flecti'ng 'si ifiics; and-for Fons reason "I prefer employ "a pentagonal prism 12 which me "be rigidly" supported eon thearrn I (l -il This prism "is arranged \ii tli itse'ntr'aiit suit fade. iii

order to obtain in the eye-pieces exit'pupils.

in each of which the whole image of the object covered by the objective lens is por-.

trayed with equal distinctness, and may be viewed by the observer placing his eye centrally of the eye-piece -in axial alinement -with the exit pupil instead of eccentrically or to one side thereof, I makethe prism 12 of suflicient width to cover the lens 5 and receive the entire pencil of rays traversing the axis of the telescope, and make provision whereby the reflected rays areselected from various-points in the cross section of the pencil while those which are not selected for reflection are-permitted to pass on and intothe primary ocular. This selection of the'rays 1S accomplished in the presentinstance by covering spots' or points of the reflecting surface and distributing these over said surface in such a way that approximately one-half of the total area of thesurface remains'clear and unobstructed to permit the passage of light rays therethrough. The covering or spotting is preferably formed by a coating of plating or silvering on the surface'le applied either in the form of bands as indicated-by 16 in Fig. 3, or by spotting the surface as indicated in Fig. 5. The precise arrangement ofthe bands or spots is not essential so long as they are so proportioned and placed that about one-half of the total rays will be reflected from points distributed throughout the whole cross sectional area of the penczll as distinguished from being all taken from one side or the center of the pencil.

These bands, or spots, increasethe reflective power of these points of the surface 14 which they overlie,wwhile the intervening transparent portions permitthe emergence of the light rays permitting these to pass on to the primary ocular.' The surface 15 is preferably silvered completely but it may be left uncoated.

In conjunction with the prism 12 I employ another prism 17 which is'preferably cemented with one of its surfaces in contact with surface 14, said prism 17 being so shaped that the rays of light passing thereinto from the unobstructed portions of the surface 14 will continue in the true axis of the telescope and will also be corrected to prevent chromatic aberration. The silvering of portions of the surface 14 of the prism 12 in the manner illustrated, and employing with said prism the secondary prism'17, produces the same result as would be accomplished should a plurality of. very narrow prisms be employed and arranged with air spaces between them through which 'a portion of the rays of light could-pass unobstru'ctedly to the primary ocula'r, but from a practical standpoint such an equivalent arrangement of prisms possesses many disadvantages, particularly on account of the necessary delicacy of the parts and the difficulty of'rigidly supporting them in accurate position, besides the fact of cutting oft an undue amount of light rays.

. A material'advantage is obtained by intercepting the entire pencil of rays and selecting from across the entire width of the f pencil portions which are suflicient-to accurately. portray the image in' the secondary ocular, and likewise leaving an equal portion of rays from different portions of the entire pencil which will pass uninterruptedly into the primary ocular, since then in both oculars the exit pupil will. be circular in outline, a correct view of the image formed which may be viewed by the observer placing his eye in direct axial alinement with either of the eye-pieces. The silvered portions of the prism 12 should be only of such a width that the images of them appearing in the eye point willbe covered, or spanned, by the pupil of the observers eye, so that he will, in effect, look through or between said im ages and observe the'image of the object itself beyond said images of the silvered portion. The latter are only visible when ones eye is withdrawn sufficiently from the eye point to observe the exit pupilinstead of the image focused at the eye point.

I claim as my invention:

l. The combination with a telescope comprising an objective lens and 'two ocular lenses, of a pris'm'arranged to intercept the entire pencil of'rays from the objective lens having a plurality of spaced reflecting sur- 2 faces receiving and directing a portion of the rays into one of the oculars, the portion of the prism between said surfaces permitting the direct passage of the remaining rays to the other ocular.

2. The combination with a telescope lens I system comprising objective. and eye-piece lenses, of a secondary eye-piece lens located with its axis at an angle to the axis of the lens system, a prism located in the axis of j the lens system and having twocoacting surfaces, one of which is provided with alternately spaced clear and reflecting portions, said portions serving to permit part of the rays to traverse the axis of the telescope and to direct part of said rays into the secondary eye-piece.

3. A telescope comprising an objective lens, a primary ocular lens system arranged behind it and a secondary ocular lens system located at one side of the axis of the objective lensin proximity to the primary ocular, a prism having coacting reflecting surfaces for directing rays of light from the ob e ctive into the secondary ocular one of said primary ocular.

4. The combination with a telescope com prising an objective lens and two separate eye-piece lenses, of means for reflecting" a portion of the rays from the objective lens into one of the eye-piece'lenses comprising a reflecting surface composed of a plurality of separated reflecting spots interposed in the pencil of rays.

5. The combination with a telescope comprising an objective lens and two separate eye-piece lenses, of means for forming images at both eye-pieces comprising a transparent surface arranged across the pencil of rays passing, from the objective lens having a plurality of spaced reflecting spots intercepting and directing portions from the entire pencil of rays into one of the eye-piece lenses, the remaining rays passing to the other eye-piece. J

6. The combination with a telescope comprising an objective lens and two separate eye-piece lenses, of means for forming images at both eye-pieces comprising a' prism extending across the pencil of rays from the objective lens having coacting reflecting surfaces for directing rays into the eye-piece lenses of one of said surfaces, being covered in places to provide alternately separated clear spaces and reflecting spots, the former permitting some of the rays to pass directly to one of the eyepiece lenses and the latter reflecting the remaining rays to the other eye-piece lens.

l he combination with a telescope having an objective lens and two ocular lenses, of a prism intereeptii'ig the entire pencil of rays from the objective lens having coasting reflecting surfaces, one of which is provided with alternately spaced clear and covered portions, the former permitting some of the rays to pass through the prism and the latter reflecting the remaining rays, and a second prism cooperating with the clear portion of said surface to control the direction of the rays emitted therefrom.

8. In a. telescope, the, combination with an objective lens, a primary ocular located in alinernent with the optical axis thereof, and a secondary ocular arranged at an angle to said axis, of a prism disposed in the axis of the telescope and intercepting the entire pencil of rays'having two coacting surfaces for directing rays into the secondary ocular, one of said surfaces being provided with spaced clear and covered portions, and a second prism receiving the rays passing through the clear portions ofsaid surface and directing them into the primary ocular.

FREDERICK B. SAEGMULLER.

lVitnesses \VILIJAM G. Woolnvon'rii, DANIEL M. Snrmr, 

